Institute of Biomedical Engineering, College of Electrical and Computer Engineering, National Chiao Tung University, Hsinchu, Taiwan.
Graduate Institute of Biomedical Informatics, Taipei Medical University, Taipei, Taiwan.
Comput Biol Med. 2018 Nov 1;102:390-395. doi: 10.1016/j.compbiomed.2018.08.016. Epub 2018 Aug 16.
Chronic hypertension is a multifactorial disease that is highly associated with cardiovascular disorders. Physical activity, such as long-term exercise, is advocated as a treatment for hypertension, but the responses of different age groups to long-term exercise are unknown. We used aged spontaneous hypertensive rats (SHRs, 80 weeks old) to test the hypothesis that long-term exercise compensated for deficient autonomic control and reduced susceptibility to ventricular tachycardia (VT) and ventricular fibrillation (VF) in this animal model. The aged SHRs were divided into control and voluntary exercise groups. Ambulatory electrocardiography was recorded for the heart rate variability (HRV) analysis. Programmed stimulation was applied to exposed hearts to induce ventricular arrhythmia in situ. Then, the hearts were isolated for an optical mapping study. The results showed that increased HRV indices were broadly related to vagal dominance in the high-intensity exercise group. Exercise altered the electrical propagation dynamic properties, such as the action potential duration restitution (APDR). Furthermore, the VF inducibility decreased with increased exercise intensity. Taken together, our results suggest that long-term exercise reduces the risk of arrhythmogenesis in aged SHRs through enhanced vagal control and stabilized electrical dynamics.
慢性高血压是一种多因素疾病，与心血管疾病高度相关。身体活动，如长期运动，被提倡作为高血压的治疗方法，但不同年龄组对长期运动的反应尚不清楚。我们使用老年自发性高血压大鼠（SHRs，80 周龄）来检验长期运动是否能补偿自主神经控制不足，并降低这种动物模型对室性心动过速（VT）和心室颤动（VF）的易感性的假设。将老年 SHR 分为对照组和自愿运动组。记录动态心电图以进行心率变异性（HRV）分析。对暴露的心脏进行程控刺激，以在原位诱导室性心律失常。然后，将心脏分离进行光学映射研究。结果表明，HRV 指数的增加与高强度运动组的迷走神经优势广泛相关。运动改变了电传播动力学特性，如动作电位时程恢复（APDR）。此外，随着运动强度的增加，VF 的可诱导性降低。总之，我们的结果表明，长期运动通过增强迷走神经控制和稳定电动力学降低了老年 SHR 心律失常发生的风险。
